This invention relates to a rocket-fired visual signalling apparatus and method and more particularly to an apparatus employing a rocket to drag a streamer into the air to spread out the streamer over trees and the like for visibility by air or ground-based personnel.
Search and rescue crews appear to have difficulty in rapidly locating lost or missing people. Every year hikers, skiers and hunters etc. become lost, injured, or both, in terrain inhospitable to search and rescue crews. Typically a lost person is not declared missing for hours before a search is initiated.
After a person has been declared missing it is often too late in the day to start a search, and a full scale search usually cannot be initiated until the following day. Meanwhile, the lost person has usually been travelling on foot or on skis and only when night falls does the person come to accept that they are lost, at which time it is too dark to proceed and the person is cold, tired, and faced with spending the night outside, unprotected.
Normally, a lost person will seek the protection of heavy timber to get out of the wind and/or snow and/or rain which severely hampers any ability to be seen by a search crew. If the person has been hurt and is unable to move or relocate to an area where an air or ground search can locate them their chances of being located are remote. If the person is unconscious, a response cannot be given in the event that a searcher calls and the prospects of being located are further reduced. Events of this nature can allow searchers to pass within a very close distance of the victim with neither party becoming aware of the other.
Emergency signalling devices are available; however, each has its advantages and disadvantages. For example, flares are relatively compact to carry, but flares burn for only a few seconds, providing only a very short window of time in which to be recognized. Due to this short window, flares are difficult to see from an aircraft because if a pilot or spotters in the aircraft are not looking in the direction of the flare at the time the flare is burning, the flare will not be noticed. Emergency locator devices which emit high frequency radio signals are also available but are relatively expensive and some are bulky and impractical to carry and depend on the reliability of batteries. Other methods of signalling include balloon launched streamers; however, balloons are susceptible to being carried away by winds, cannot be used in some weather conditions and require a clear space for launching. Furthermore, the flight path of a balloon cannot be accurately controlled.
What would be desirable is a signal streamer which can be spread out above the trees and which generally stays in the vicinity of the lost person and which remains visible for a long period of time, even in high wind conditions, rain and snow, which is relatively easy to carry, which is inexpensive, and which does not rely on external power sources such as batteries. Furthermore, a device with long shelf-life and no maintenance requirement is desirable.
U.S. Pat. No. 4,741,243 to Snider discloses a line launcher for launching a line spool provided with a length of line, toward a target. This device employs a ballistic method to launch a projectile containing the line spool, from a conventional marine flare gun. However, it appears the line is of rather small gauge to be seen by air or ground rescue parties and it requires that the user carry both a flare gun and the projectile, which would be cumbersome to hikers and skiers.
U.S. Pat. No. 4,505,179 to Nelson et al. discloses a line throwing device for launching a projectile from a riot gun or similar tubular launching device. The projectile includes a shotgun primer cap and a rocket motor for launching and propelling the projectile respectively. This device employs stabilizing fins for stabilizing the flight path of the projectile and employ a bridle for evenly pulling the line. However, the stabilizing fins would make the device impractically bulky to be carried about by a hiker or skier and further would require that that person carry a rather large riot gun or other large launching device. Furthermore, the device is intended to throw a line for conventional purposes rather than a streamer for visibility purposes.
The present invention overcomes the difficulties with prior art devices and addresses the need discussed above.